Thoughts on the MEMS Technology Session at SEMICON Japan 2009

If you are going to visit Japan after a long (OK, a year) absence, then you should try to combine your niece’s wedding in Kyoto with a visit to the ancient capital, Nara, brilliant late Fall colors, the Cornell Club of Japan American Holiday Dinner, and SEMICON Japan 2009 all in the same trip.

That, and eat delicious Japanese food for breakfast, lunch, and dinner. And arrange for a hot spring visit, if you can work that in too.

I’ll save the hot spring for next time – our family motto is “You should always leave wanting a little bit more.” But I did manage pretty much everything else.

The wedding was fabulous. Three complete changes of clothing for my niece Megumi: Japanese bridal white, autumn kimono color, Western bridal white. A perfect ripe persimmon ends the long kaiseki lunch. At the late party that follows, Japanese ice-breaker games, various forms of singing, and loud thumping music, but no dancing, a surprise.

Been to Nara ever? No? Go! I like the sense of space you get in Nara, particularly in the park around Todaiji, the temple housing the large statue of Buddha. The park deer are cute, then annoying, but they do seem healthier now than in years past (I hated that three-legged deer thing), and still look just as well fed as before, fed mostly now by the many tourists visiting from China.

I thought Autumn colors were long over this year (I saw Sierra Nevada aspens already turned bright yellow in mid-September), but in Nara, in Kyoto, and even in Tokyo, the color keeps on coming. Either loose and wild, or in carefully tended and arranged gardens, the momiji, Japanese maples, are magnificent.

So on to the show! From Tokyo Station to Makuhari Messe, site of SEMICON Japan, you ride the same train as if you were going to Tokyo Disneyland. Train door closing songs in Japanese train stations change with the seasons, and usually are of an homage-to-nature ambient flavor (just how much in royalties did Brian Eno receive for writing the Microsoft Windows start-up shut-down jingle?), but at the Tokyo Disneyland station I break into a broad smile because the train doors close to the sound of Zip-a-Dee-Doo-Dah, Zip-a-Dee-Ay.

And you can’t help smiling at that. Thanks Uncle Walt!

I’m booked all-day Wednesday 02 December 2009 at the SEMI Technical Session devoted to MEMS topics. Our leaders for the day are Dr. Enjoji, from Tokyo Electron, and Professor Esashi, Esashi-sensei, from Tohoku University. The morning session features all Japanese papers, given in Japanese, with no simultaneous interpretation, and my Japanese isn’t good enough now (was it ever?) to keep up much with what’s being said.

But I do manage to learn interesting things about a new etch technology based on reactive ion clusters projected onto wafer surfaces by a kind of reactive ion cluster gun. Advantages? No plasma means no plasma damage, and, if you introduce tilt between the ion cluster trajectory and the wafer surface, you end up with angled etching. Plus, silicon etch rates exceeding 40um/min, with 2000:1 (!) selectivity to the etch mask. Seems like there’s a lot to like about that. I want to be the second customer ….

After lunch (obento, packaged box lunch, with cold green tea, all very tasty), we move into the afternoon MEMS session, which features speakers from in and outside Japan, with simultaneous interpretation services available in both English-to-Japanese and Japanese-to-English. (Simultaneous interpreters must be the hardest working folks in show business.)

I think heterogeneous integration is the way 3D-IC manufacturing techniques are going to launch into the commercial mainstream, and now there’s a Heterogeneous Technology Alliance (Malier, CEA-LETI) to put wind into those sails. I’ve said this before, but when you step outside US-centric thinking and look to see what Japan and the EU are doing with 3D-IC, it’s all about adding functional value, or introducing novel products, via heterogeneous integration. Don’t know why we don’t hear more about heterointegration from the home team sluggers. (Roger Grace has more to say on this subject – look for his piece in the February 2010 issue of Electronics Products.)

And the Intel – Nanochip probe-based memory technology gets another mention. Probe-based memory seems to have more lives than cats, or more legs than millipedes. But it’s been a very long runway. A very long runway indeed.

Most interesting paper of the afternoon MEMS session? Hands-down it’s the paper on roll-to-roll printed MEMS (Kopola, VTT). (I have a great chat later over a few glasses of sake at the SEMI President’s reception with Harri and his colleague). Printed electronics, flexible substrates, printed MEMS displays, paper making and printing technology from Finland’s vast boreal forests industry. And world-class research institutes. That’s critical mass.

I like PZT. I like PZT-based actuators. I liked hearing about inkjet print heads with PZT actuators (Oh, Samsung).

Not on the original agenda, but on today’s program, is the paper from SPP (Sumitomo Precision Products) on 300mm DRIE. Susumu Kaminaga, SPP’s President, is sitting directly in front of me; it’s one small world here for sure in this corner of the silicon DRIE equipment business. Does 300mm MEMS fabrication make sense? Hard to think so now, with so much room for MEMS fabrication still to grow into even 200mm wafer processing; less than 25% of all MEMS processing in 2008 is at 200mm, leaving a 75% share for 150mm fabrication and below, according to Yole Developpement and the Information Network. We’ll see. 300mm MEMS tools seem like big iron to me. Too big iron for now.

Which is the point I hope I make in my presentation, on a 3rd Generation ICP Source optimized for 200mm silicon DRIE work. Let’s do 200mm silicon DRIE even better than before, on 200mm tools.

Professor Esashi is such a force of nature that he is able to run through something like 45 slides in 15 minutes during his presentation on the great things in progress Sendai-way, leaving us all gasping for breath at the vast scope and breadth of his work at Tohoku University. Esashi-sensei, gambatte!

What’s the worst consequence for going last in a series of papers on similar topics? It’s often that the items you cover in your paper’s introduction have already been covered and covered again by the speakers before you. How to come out on top then in a situation like that? How about that every speaker before you used data you yourself produced and published?

Which is how it goes for Jean Christophe Eloy, Yole Developpement. Jean Christophe takes it nicely in stride, a true gallant, that many of his slides have already been used by this afternoon’s speakers, and we all laugh when we recognize the truth. No case of stolen thunder; rather, it’s like we’ve been following a broad stream of knowledge today, followed it straight up to its source.